fix: no-unresolved check import() (fixes #2024)

Author: aladdin-add

tests/src/rules/no-unresolved.js

@@ -1,6 +1,6 @@
 import * as path from 'path';
 
-import { test, SYNTAX_CASES } from '../utils';
+import { test, SYNTAX_CASES, testVersion } from '../utils';
 
 import { CASE_SENSITIVE_FS } from 'eslint-module-utils/resolve';
 
@@ -93,7 +93,6 @@ function runResolverTests(resolver) {
                             '\'./reallyfake/module\'.' }],
       }),
 
-
       rest({
         code: "import bar from './baz';",
         errors: [{ message: "Unable to resolve path to module './baz'.",
@@ -382,3 +381,22 @@ ruleTester.run('no-unresolved syntax verification', rule, {
   valid: SYNTAX_CASES,
   invalid:[],
 });
+
+// https://github.com/benmosher/eslint-plugin-import/issues/2024
+ruleTester.run('import() with built-in parser', rule, {
+  valid: [].concat(
+    testVersion('>=7', () => ({
+      code: "import('fs');",
+      parser: require.resolve('espree'),
+      parserOptions: { ecmaVersion: 2021 },
+    })) || [],
+  ),
+  invalid: [].concat(
+    testVersion('>=7', () => ({
+      code: 'import("./does-not-exist").then(() => {})',
+      parser: require.resolve('espree'),
+      parserOptions: { ecmaVersion: 2021 },
+      errors: ["Unable to resolve path to module './does-not-exist'."],
+    })) || [],
+  ),
+});

utils/moduleVisitor.js

@@ -36,10 +36,17 @@ exports.default = function visitModules(visitor, options) {
 
   // for esmodule dynamic `import()` calls
   function checkImportCall(node) {
-    if (node.callee.type !== 'Import') return;
-    if (node.arguments.length !== 1) return;
+    let modulePath;
+    // refs https://github.com/estree/estree/blob/master/es2020.md#importexpression
+    if (node.type === 'ImportExpression') {
+      modulePath = node.source;
+    } else if (node.type === 'CallExpression') {
+      if (node.callee.type !== 'Import') return;
+      if (node.arguments.length !== 1) return;
+
+      modulePath = node.arguments[0];
+    }
 
-    const modulePath = node.arguments[0];
     if (modulePath.type !== 'Literal') return;
     if (typeof modulePath.value !== 'string') return;
 
@@ -87,6 +94,7 @@ exports.default = function visitModules(visitor, options) {
       'ExportNamedDeclaration': checkSource,
       'ExportAllDeclaration': checkSource,
       'CallExpression': checkImportCall,
+      'ImportExpression': checkImportCall,
     });
   }